On Wed, 2005-03-30 at 16:28, Stephen Hemminger wrote:
> This patch cleans up the netif_rx and related code in the network
> receive core.
>
> - Eliminate vestiges of fastroute.
> The leftover statistics no longer needed.
>
> - Get rid of high/med/low threshold return from netif_rx.
> Drivers rarely check return value of netif_rx, and those
> that do can handle the DROP vs SUCCESS return
>
Please leave this feature in. Drivers that used it have moved on to a
better life under NAPI; however, it is still useful for anyone who wants
to take heed of congestion. And infact it is highly advisable for
anyone not using NAPI to using it.
In other words: the work should be to convert users of netif_rx and not
to get rid of this feature.
> - Remove dead code for RAND_LINE and OFFLINE_SAMPLE
>
OFLINE SAMPLE can go. The other refer to my comments above.
> - Get rid of weight_p since setting sysctl has no effect.
> Increase default weight of netif_rx path because it can receive
> packets from multiple devices and loopback.
>
Same here.
> - Separate out max packets per softirq vs. max queued packets.
> Today, netdev_max_burst is used for both. Add new parameter
> that is for the per-cpu max queued packets.
>
> - Increase queue defaults to meet modern CPU speeds.
> Make max_backlog be about 1ms, and max_queue be about 10ms
>
kind of hard to compute what 1 or 10 ms in packet count. But probably
justfied to make the default larger.
> - Switch to pure drop tail when queue fills.
> Better for TCP performance under load to drop a few packets
> then go into full discard mode.
>
Like discussed in that thread with person who enhanced the SACK queue
traversal that for a serious use a TCP user really oughta migrate to a
NAPI driver.
cheers,
jamal